I was just looking that up today and reading other threads- I believe the consensus was satin and/or semi-gloss, (which I believe are the same). I've always used satin black. Here's one with black satin paint.

Edit: Apparently, a black lacquer was used at the factory and lacquer would be more glossy than satin, I believe.

To me, it depends on how bad they are. Purists will certainly not want to alter the original paint missing from the hoop. However, if you plan to play them and clean them up, it really doesn’t effect the value. Typically, I clean the inlay first and tape off before sanding with an 80 or 100 grit by hand. This removes loose paint and smooths out the surface first. If needed, I tape again, depending how the sanding went.

Prime first and look for imperfections, sand again as needed, then prime again. By now, I’m usually ready for paint, I have used both satin and gloss and prefer the look of the gloss as I clear coat a few times after 4 or 5 passes with the paint. Results are amazing and really help top off a complete tear down and polish of all the hardware.

It’s a tedious process, but well worth it!

I use black lacquer from a spray can. Most well stocked hardware stores still carry actual lacquer in clear, white, and black. I just bought a new can the other day for use on one of my projects. Nitro Lacquer such as DuPont Duco is what was originally used on these (as opposed to enamel and other more modern types of paints). I'm not sure if the stuff you can buy today in the spray cans is nitro lacquer (it probably isn't) but it seems to work. Unpolished lacquer has a more satin look to it than lacquer which has been finished off with wet sanding and polishing. They did not polish the hoops, just painted them.

Thanks all. Very informative.

Semi gloss has a bit more sheen than satin and are not the same. The next level of sheen below satin is egg shell, I believe.

Thank you. Very helpful and means I can put the right finish on my BoP 64 hoops.